I think you messaged me on ebay about this as im the seller. Sorry you don't like repros but lots of people do.

As I mentioned in my ebay reply to you which you haven't mentioned here, ill go in to a little bit more detail on the tell tale signs. I also mention some comments on the auction itself.

The top part which protrudes from the hatch is painted to match the existing green. Painted, not moulded in that colour. Hard to tell the difference here.

The part which slots in to the hatch is also painted to match the existing, as it slots in there will be some light marks on this part as its fitted. This is one slight telltale sign.

The base of the aerial is unpainted where it is clipped away from the print support and this is the main tell tale sign. The original resin colour (either translucent red, grey, or translucent green) is visible at this bottom point.

If youre unsure if one you are looking at is repro or not simply ask the seller to take a pic of the bottom of the aerial in situ on the hatch and you can tell as the colour wont match the hatch surround, or ask them to remove and take a pic / perhaps also ask them to smudge the aerial on a white piece of paper to see any paint come off on the paper.

Ive sold lots on ebay and via FB groups and ive seen lots of independent comments on posts showing off their "complete" ATC but them also mentioning how the bottom isn't painted so its identifiable as repro.

There is another seller on actionfiguresupplies (the website may have changed as he seemed to have some issues with the site / a few complaints I saw on FB groups where people were waiting for packages) who has his own version. This shape doesn't match the original and its in an entirely different green. The 3d print is also not smooth but are also easily distinguishable.